Question: Simplify the following expression: $k = \dfrac{2z^2 + 3yz}{4z^2} + \dfrac{3xz - z^2}{4z^2}$ You can assume $x,y,z \neq 0$.
Answer: Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{2z^2 + 3yz + 3xz - z^2}{4z^2}$ $k = \dfrac{z^2 + 3yz + 3xz}{4z^2}$ The numerator and denominator have a common factor of $z$, so we can simplify $k = \dfrac{z + 3y + 3x}{4z}$